Method and means for actuating an element of a weaving machine



May 30, 1967 E. PFARRWALLER 3,322,153

METHQD AND MEANS FOR ACTUATING AN ELEMENT OF" A WBAVING MACHINE Filed April 3, 1964 6 Sheets-Sheet I jnvemor: [Kw/N FFARRWA 115R y 0, 1967 E. PFARRWALLER 3,322,158

METHOD AND MEANS FOR ACTUATING AN ELEMENT OF A WEAVING MACHINE Filed April 8, 1964 6 Sheets-Sheet 2 jnvenfar: fRw/A PM HRWALLER May 30, 1967 E. PFARRWALLER 3,322,158

METHOD AND MEANS FOR ACTUATING AN ELEMENT OF A WEAVING MACHINE Filed April 8, 1964 6 Sheets-Sheet 3 I80 360lo 780 360% 180 360%: 180

Yrwenfor: fRw/N F ARRWAL l [R ATTGRNEX May 30, 1967 E. PFARRWALLER METHOD AND MEANS FOR ACTUATING AN ELEMENT OF A WEAVING MACHINE 6 Sheets-Sheet Filed April 8, 1964 mu 7 Lw m 8/ .7 H w 2 0 1 0J0 5 3 .d ,9 nm 6 W14 saw 0 WA 0 m 9 6 7 H! .m a m o F m. w .w n

May 30, 1967 E. PFARRWALLER 3,322,158

METHOD AND MEANS FOR ACTUATING AN ELEMENT OF A WEAVING MACHINE Filed April 8, 1964 6 Sheets-Sheet T:

Jnventor:

May 30, 1967 E. PFARRWALLER 3,322,158

METHOD AND MEANS FOR ACTUATING AN ELEMENT OF A WEAVING MACHINE Filed April 8, 1964 6 Sheets-Sheet 6 II E7998 737 140 v ,1 a I 9913; m 133 I32 m I *rsa fwm Pm RPM/AMER United States Patent Ofilice 3,322,158 Patented May 30, 1967 METHOD AND MEANS FOR ACTUATING AN ELEMENT OF A WEAVING MACHINE Erwin Pfarrwaller, Winterthur, Switzerland, assignor to Sulzer Brothers Limited, Winterthur, Switzerland, a corporation of Switzerland Filed Apr. 8, 1964, Ser. No. 358,260 7 Claims. (Cl. 139-4) This invention relates to a weaving machine comprising means to momentarily separate a mutually contacting moving element and its non-positively connected supporting means. The means is moved by the drive of the weaving machine through a steering arrangement whereas, the moving element is submitted to a power means, for instance a spring; the power means, in the case where mutual contact is broken, causing movement of the moving element.

More particularly, the invention relates to a weaving machine as above wherein the part of the steering arrangement which causes the movement of the supporting means for separating it from mutual contact with the moving element includes a steering groove which has an inclination in the sense of an augmentation of the movement to separate. The inclination is made greater than the inclination which is necessary to eifect the mutual contact of the supporting means with the moving element while only under the influence of the power means in such a manner that before the moving element reaches its position of action a permanent separation of the supporting means from the moving element is effected.

The separation of the points of mutual contact on the moving element and on the supporting means reduces or eliminates the possibility of the transmission of an undesirable force effect between the two points while they are separated. Such an undesirable elfect may arise, for example, from the fluctuations in the movement of the supporting means due to uneven running of the drive of the weaving machine which may, for instance, occur during certain angles of the cycle due to the high inertia of elements operated by said drive.

Preferably, the separation at the point of mutual contact between the moving element and the supporting means may be greater than the maximum amplitude of oscillation at said point.

According to another aspect of the present invention, a weaving machine may have healds, a card dobby including a card band, reading needles for reading said card band, lifting needles for lifting the reading needles and a power means for pushing the reading needles wherein the reading needles are pulled out of the card band all together by a pulling bar and lifted by a lifting rail. The pulling bar acts as the supporting means and is connected with a steering arrangement while the lifting needles act as the moving element.

A further application is for a weaving machine having gripper shuttles, a lever, means including a retractor for feeding weft thread to said shuttles, said retractor being connected to said lever for actuation thereby, a cam having a cam surface and a cam follower whereby said supporting means are constructed as cam surface operatively connected to said drive of the weaving machine for rotating said cam surface by said drive, being arranged, for example, on a drum, and said moving element made as a cam follower engageable with said cam surface and connected to said lever for swinging the latter according to the configuration of said cam surface.

Preferably the cam surface in the form of a groove like an S-curve shows a change of the augmented inclination of the steering cam surface from one side of the S-curve to the other.

A third possible application is to a weaving machine which has weft thread changing means including a locking disc connected to an energy accumulator forming the power means, the disc having a plurality of indentations adapted to receive a locking roller, means operatively connecting the locking roller to the drive of the weaving machine whereby the locking roller functions as the supporting means and the locking disc as the moving element, the cam surface or steering arrangement effects the separation of the locking roller from the locking disc only in the second half of the dislocking way.

The invention will be explained in more detail with reference to FIGURE 1 of the accompanying drawings, and although the invention may be carried into practice in various ways, one particular weaving machine to which three mechanisms of the invention have been applied will now be described by the way of example with reference to FIGURES 2 to 12 of the accompanying drawings.

In the drawings:

FIGURE 1 is a diagram showing the movement of the point of contact of a moving element of a weaving machine and of the point of mutual contact of a supporting means thereof, when there is a non-positive connection between the two and also when they are moving separately from one another;

FIGURE 2 is a section through the heald plane of a weaving machine having a dobby fitted and shown in elevation;

FIGURE 3 is a section through the reading device of the card band of the dobby shown in FIGURE 2 and through the control system for the lifting hooks;

FIGURE 4 is a cross-section through the needle carrier shown in FIGURE 3 on a larger scale;

FIGURE 5 is a diagram showing the movements of various means of the weaving machine, referred to the angular position of the main shaft of the machine;

FIGURE 6 shows a device, controlled by the dobby shown in FIGURE 2, for changing the weft thread with a locking roller engaging in the indentations in a locking disc connected to the weft thread change drum;

FIGURE 7 shows an indentation and the locking roller from FIGURE 6, on a larger scale;

FIGURE 8 is a diagram showing the position of the points of contact of the indentations of the locking disc and the locking roller from FIGURE 6, and showing the dynamic effect of the locking disc upon the locking roller with the corresponding travel components;

FIGURE 9 shows the travels of the points of contact of the wall of an indentation and the circumference of the roller shown in FIGURE 6, before and after separation.

FIGURE 10 shows a thread retractor of the weaving machine and a grooved drum for positioning the thread feeders;

FIGURE 11 shows a development of a portion of the groove and the drum shown in FIGURE 10; and

FIGURE 12 is a diagram showing the travels of the points of mutual contact of the lever roller and of the groove wall of the mechanism shown in FIGURES 10 and 11.

If two parts to be moved are not connected by some form of joint but nevertheless have a non-positive connection between them such that one can affect the other, theymay possess at least one common point of mutual contact where a force can be transmitted from one part to the other. If the effect of the non-positive connection exists, for example, because one part serves to move the other, and if the movement comprises acceleration, deceleration and a standstill, the relationship may be effected by yielding pressure between a groove and groove roller, or the like.

If the travels are only partly common and partly different, a separation of one part from the other occurs at the transition from the common to the separate travel. For example, one part may come to a standstill at a stop element whilst the other continues to move. In another case, if one part serves to block the movement of the other part, the separation occurs when the blocking element is completely retracted from the blocked part.

During the common travel, the two parts having mutual contact are subject to mutual influence in their movement. For example, if the movement of a driving part is subject to oscillation, the movement of the driven part will oscillate correspondingly. This may lead to faulty operation, as is apparent from the examples described below.

It is the object of the invention to provide a Weaving machine which avoids such faulty operation by a special control system of the movement of themoving element or of the supporting means, or both, which eifects a premature separation of the supporting means from the moving element in the area of the otherwise common travel by increasing the inclination of a cam surface of a steering arrangement in the sense of an augmentation of movement of the supporting means.

This premature separation can be brought about at any point of a normally common travel, either at commencement or at a subsequent point when the moving element moves through the action of the power means independently of the supporting means which is driven by the drive of the weaving machine through the steering arrangement. However, this premature separation may also be cancelled before the end of the normally common travel, so that exclusively that region in which an undesirable force efiect is transmitted from the supporting means to the moving element, or vice versa, is travelled through without mutual contact between the two. These possibilities will now be described in greater detail with reference to FIGURE 1.

The moving element 1 in FIGURE 1 is at times nonpositively connected to the supporting means 2 which is moved by the drive of the weaving machine and through a steering arrangement, and at times the moving element executes a movement independent of the movement of the supporting means through a power means, such as, a spring, independent of the machine drive.

Moving element 1 moves from s to s and supporting means 2 from s to s Whereas both have the right-hand terminal position in common, the moving element has the left-hand terminal position s and the supporting means has the different left-hand terminal position s The abscissae represent the travel s, and the ordinates are a measure of the time t.

In the lower part of the diagram shown in FIGURE 1 which represents the movement of a moving element and supporting means during mutual contact, the supporting means moves alone from s to s beginning at the time t encounters the moving element at t and takes it to the right until both reach the terminal position s at the time t From t to t the moving element is non-positively connected to the supporting means and is moved to the right against the power means to which the moving element is submitted, for example, a spring 3. The moving element and supporting means have mutual contact at the point p and move along the line L The points of contact p on the moving element are designated by a cross, and the points of contact p on the supporting means are designated by a small circle.

The line L in the central portion of the diagram represents the movement of the point of contact p when the moving element moves along from s to s by the action of the spring 3; moving element 1 encounters a stop element at s and comes to a standstill. The line L has been redrawn in mirror image relationship as line F for comparison with the line L It is apparent from the comparison that the line L exhibits non-uniform fluctuations in velocity which are displaced from the line F and are also greater than the accelerations and decelerations necessary for the reciprocating movement. This nonuniform travel is produced by the weaving machine drive, as will be shown below with reference to FIGURE 5. This non-uniform travel also produces an effect upon the moving element along the line L On the other hand, during the movement of the two' from right to left in the central portion of the diagram, a premature separation of the point of contact p from the point p or the supporting means from the moving element, occurs from s onwards under the influence of the steering arrangement connected to the drive of the weaving machine. Consequently, the non-uniform travel of the supporting means no longer has an influence upon the travel of the moving element. The travel of the moving element from s to s as shown by line L occurs exclusively by the action of the spring 3 regularly. and with constant acceleration until the moving element is in contact with a stop element at the time 12;. Supporting means whose movement is shown by line L reaches its left-hand terminal position s at time t Any undesirable force effect by the supporting means upon the moving element is thus eliminated.

The line L is located below the line L and the distance travelled by the point of contact p from at a given time z is greater than the distance travelled by the corresponding' point p so long as the latter distance is other The premature separation of the parts 1 and 2 at their 7 points of contact p and p may take place at any time between the terminal positions s and s and may also be cancelled if the undesirable force effect becomes insignificant or absent during the remaining part of the travel. This is shown by the lines L and L in the upper portion of the diagram FIGURE 1. The lines L and F in the lower portion between .9 and s are almost coincident; this means that the drive of the moving element by the supporting means is almost as constant as by the spring 3, so that no separation is as yet necessary from s to s or from t to 1 The separation occurs only at s at the time t The line L runs below the line L and the moving element moves with constant motion by the action of the spring 3 as far as the position s 'at timfi is.

Because the supporting means is already undergoing deceleration, or because the position of the moving element in this section may possibly no longer so require, the parts 1 and'2 are again in contact from s to s until it is necessary for the normal separation to occur at s due to the standstill of the moving element at the stop element, so that supporting means can complete its travel to the position s at the time t Although this case of common travel towards the end of the movement is entirely possible in the case of the example to be described with reference to FIGURES 2 to 4, it would be quite impossible in the case of the example to be described with reference to FIGURES 6 to 9.

FIGURES 2 to 4 show various parts of a loom 10. FIGURE 2 which is a section through part of the loom 10 in a heald plane shows a heald 11 in conjunction with a bar 12 which moves up and down in a fixed guide element 15 during swinging of a bell crank lever 13 which is connected to the bar 12 by means of a link 14. The bell crank lever 13 is connected by a linkage 16 to the respective lever 17 of a card dobby 18, the lever 17 being adjustably connected to a link 19 which is pivoted to a rocking lever 21.

A timing shaft 22 is driven at constant speed by the main shaft, not shown, of the weaving machine 10, the main shaft being detachably connected to the weaving machine drive, i.e. an electric motor, by means of a friction clutch, not shown. Whereas the drive of certain parts and particularly of the slay is derived from the main shaft, the timing shaft 22 drives the shuttle picking mechanism, the control of the warp beam and of the cloth beam, and other devices, not shown. The shaft 22 also drives a shaft 24 by a chain transmission which has a step down ratio which causes the shaft 24 to rotate at half speed. The shaft 24 drives, in the interior of the card dobby 18, a lifting device which operates with reciprocating lifting beams, onto which lifting hooks, controlled by a control device for the heald movement which will be described hereinbelow, are hooked in dependence upon the perforations of a card band 32. The lifting hooks directly or indirectly actuate one rocking lever 21 per heald.

The shaft 24 carries a worm gear 25 which drives a control shaft 26 carrying a timing gear 63 which meshes with a gear 65 on a card cylinder 27. The latter is driven at the same speed as the main shaft of the weaving machine 10.

The pattern card reading device shown in FIGURE 3 comprises the card cylinder 27 around which passes the perforated card band 32, and card-reading needles 28 which are mounted horizontally in a needle carrier 29 secured to the frame 31. The needle carrier 29 comprises a part 33 having bores wherein lifting needles 34 provided with heads 35 are suspended. As seen in FIGURE 4, each lifting needle 34 extends through a bore 36 in a collar 37 of a reading needle 28.

The lifting needles 34 are actuated by a lifting rail 38 and each needle 34 is associated with a notched bar 40 which can be hooked onto control knives 41 and 42 by actuation of the respective needle 34. The control knives 41, 42 are reciprocated by the loom drive in accordance with the arrows shown in FIGURE 3 which indicate the direction of movement of the knives 41, 42.

Each notched bar 40 is articulated to a control lever 43 which swings about an axis 44. The control lever is connected by means of links 45, 46 to a pair of lifting hooks, not shown, associated with the heald 11. When the control lever 43 is brought into the left-hand or right-hand terminal position by the notched bar 40, the one or other lifting hook is hooked onto one of two lifting beams, not shown. The two lifting beams are simultaneously reciprocated by the shaft 24. The engaged lifting hooks rock the respective lever 21 and displace the respective heald 11 via the intermediate linkage 12 to 17.

These operations are controlled on the basis of the reading of the perforations in the card band 32 by the reading needles 28. To prepare for the reading, the lifting rail 38 is brought into the lowest position I. It is secured at each of its ends to a lever arm 48 pivotable about a fixed axis 47. One of the lever arms 48 has a further arm 49 carrying a roller 51 which follows a cam 53 whereunto the roller 51 is pressed by a compression spring 52. The cam 53 is driven at constant speed by the shaft 26 in the direction of the arrow 54.

When the rail 38 is lowered, all the lifting needles 34 descend until the heads 35 rest upon the needle carrier 29; the lower ends of the lifting needles 34 are now out of the groove 39. When this has taken place a bar 55 the supporting meanswhich rotates about an axis 56, swings to the right and moves all the lifting needles 34 from the position III to the position IV, FIGURE 4, thereby releasing all the reading needles 28 from the card band 32. The reading needles 28 and the lifting needles 34 constitute the moving element. The movement of the bar 55 is controlled by a cam disc 57, FIGURE 3, which constitutes the steering arrangement having a groove 58 in which travels a roller 59 on an arm 61 fixed to the rotatable shaft on which the bar 55 is fixed. The grooved disc 57 is driven at constant speed by the shaft 26 in the direction of the arrow 62.

The card cylinder 27 with the card band 32 can now To this end the control shaft 26 is provided with an indexing gear 63, the tooth system 64 of which meshes with the tooth system of the gear 65 connected to the card cylinder 27. The gear 65 is indexed forward by the oblique portion 66 of the tooth system 64 by one tooth pitch, corresponding to the pitch of the perforations in the card band 32.

Reading of the subsequent row of holes is now possible. The bar moves to the left. The lifting needles 34 follow the card-reading needles 28 owing to the pressure of compression springs 67 (power means) acting between the collars 37 and a fixed abutment through which the needles 28 slide. If a hole is present in the band 32 opposite a needle 28, the needle 28 enters the hole 32 until the collar 37 contacts the left-hand wall of the needle carrier 29, whereby the lifting needle 34 is returned to position III. Where no hole is present opposite a needle 28, the needle rests upon the band 32 and the lifting needle 34 remains in the position 1V, FIGURE 4. The compression springs 67 are comparatively weak for avoiding damage of the card band 32.

If the lifting rail 38 is now raised once more from its position I into the position II, FIGURE 3, only those lifting needles 34 which occupy the position III, FIGURE 4, will enter the groove 39 in the rail 38. The lifting needles 34 in the position IV remain in the lower position. With the first-mentioned lifting needles 34, the associated notched bars 40 are moved out of the positions a into the position e, FIGURE 3, so that they cooperate with the control knife 41, whereas t-he.notched bars 40 associated with the other lifting needles 34 are actuated by the control knife 42. 1

Depending upon the direction of movement of the control knives 42, 41, which may be seen clearly from the arrows shown in FIGURE 3, and from the movements diagram, FIGURE 5, curve St the control lever 43 is either moved or not moved, and the associated heald is actuated accordingly.

FIGURE ,5 shows a number of movements diagrams. The line L represents the movement of the slay; each line S,, and S shows the movement of a heald; line H, shows the movement of the lifting beams; lines St show the movement of the control knives 41, 42; line H shows the movement of the lifting rail 38; line Ah shows the movement of the reading device, more particularly of the bar 55, and line K shows the stepping of the card cylinder 27.

FIGURE 5 clearly shows that during the stepping travel of the card cylinder 27 from k to k the reading device, the lifting needle 34 and the card-reading needles 28 are retained in the position IV distant from the card band 32 by the bar 55. When the angular position k is reached, the bar 55 is moved back towards the left.

FIGURE 5 clearly shows that, in the case of the angular position k of the main shaft, not only are the healds 11 in motionsee the lines S, and S but that, more particularly, the last weft thread inserted is beaten up see part A of the line L, for the movement Olf the slay. If a number of healds 11 are raised together and the slay is also made to beat up with the reed, large masses must be moved simultaneously.

This result in an abrupt increase in the torque in this angular region of the main shafts rotation. Since the drive motor is unable to deliver a corresponding torque increase instantaneously, the angular velocity may for a short time diminish to one half the normal velocity. When the weft thread has been beaten up, the great increase in torque disappears equally abruptly with the return R of the slay, FIGURE 5. Indeed, the warp tension which was increased by the beating-up actually accelerates the slay in its return R. The angular velocity of the main shaft now increases beyond the mean value and returns to this mean value only after some oscillations. These oscillations may produce, in the case of parts which are moved at thi time, oscillations which give rise to faults.

For instance, it has been found that during the reading of the card band, liifti-ng needles 34 were not caught by the lifting rail 38, although holes for the reading needles 28 associated with them were present in the row of holes to be read in the card band 32, and the associated notched bars 40 were not lifted as they should have been in accordance With the pattern on the card band 32. .The resulting defect in the woven cloth must be corrected whereby the standstill time of the loom is increased.

It is probable that lifting needles 34 which are in con-' tact with the bar 55 received, by the effect of the aforesaid oscillations during their movement to the left as viewed in FIGURES 3 and 4, such a strong acceleration directed toward the right that at the point of contact 12 FIGURE 4, the needle mass and acceleration combined to form a force directed to the right sufficient to overcome the weak force of the spring 67, so that therrelevant lifting needles 34 were thrown back sufliciently far for the needle ends to be located to the right of the lifting rail 38 when the lifting rail rose so that they were not caught in the groove 39.

In order to obviate this, a part of the groove 58 of the grooved cam disc 57 is so constructed in the region 'lifting needles reach their position of action (over the lifting bar 38) a separation of the bar 55 from the lifting needles 34 is effected. Thus, the travel of the point of contact p on the part two (the bar 55) is made greater than the travel component, other than zero, of the point of contact p on the moving element in the direction of the travel of the point of contact p on the part two. When the common point of contact is displaced, the point [1172 at the moment of separation of the parts requires consideration, FIGURE 1. The travel component of the point 1 on the lifting needle 34 in the direction of the travel of the point p of the bar 55 (the part two) did not become zero until the collar 37 came into contact with the left-hand wall of the needle carrier 29. Due to the above-mentioned design of the groove 58, the separation of the barr55 occurred prematurely. It may occur either at the commencement of the movement of the bar 55 to the left, or from a chosen point onwards, e.g., s in FIG- URE 1. After the separation, the lifting needles 34 are no longer influenced by any oscillatory movement of the bar 55. The line Ah in FIGURE also shows this premature separation. The bar 55 moves from a towards [1 whereas the lifting needle 34 does not attain its terminal position until a later moment a Consequently, the lifting rail 38 cannot commence its upward movement until the angular position it (line H coincides with the angular position a;;.

FIGURE 6 shows a further application of the invention. The card dobby 18, FIGURE 2, controls the position of two bars 68 and 69 which control a device 71 for selectively changing the weft thread to be inserted into the shed.

The bars 68 and 69 are connected by freely rotating bell-crank levers 72, 73 on a fixed axis 74, rods 76, 77 and bell-crank levers 78, 79 on rotatable shafts 75, to cylinderand piston power accumulator elements 80, 81.

The piston rods 82, 83 of the elements 80, 81 are articulated to the upper arms of bell-crank levers 86, 87, which rotate on shafts 84. The arms 88, 89 of the levers 86, 87 are connected to the ends 92, 93, respectively, of a balance lever 85 by means of the shafts 90, 91. From a pivot point 94 on the lever 85distant from the axes of the shafts 90 and 91 in the ratio l:2a rod 95 leads to acrank arm 96 fixed to an axle 97 of the weft feeder change drum 71.

The change drum 71 carries thread feeders 99a to 99d which slide in grooves 98a to 98d on the drum. They are selectively slid towards a gripper shuttle 100 by a device shown in FIGURE 10 when the relevant feeder 99 has been moved into the picking line.

The side wall of the drum 71 is provided with a locking disc 101 (moving element) which has notches 102a to 1020! which receive a locking roller 103 (supporting means) on a lever 104, to which a rod 107 is pivoted. A pin 106 on the rod 107 engages in a control groove 108 on a grooved cam disc 109 which is secured on a shaft 111a, the latter being driven at a speed equivalent to the rate of picking by the main shaft of the loom.

The arms 88, 89 cooperate with stops 110 and 111 in order to adjust the change drum 71 precisely to the chosen position so that the locking roller 103 may enter without difficulty the notches 102a to 102d which correspond to the position of the balance lever 85. The stops 110 and 111 may be adjustable.

The double-armed lever 104 rotates about a clevis pin 112 in a fork 113 on a rod 114 which slides in a stationary' part 105. The head 115 of the rod acts as a stop element so that, at normal operating conditions, a powerful compression spring 116 between the rod and the stationary part maintains the fork 113 and the pin 112 in the illustrated operating position.

If for. any reason the locking roller 103 should fail to be positioned opposite one of the notches 102 when the roller is moved to the right by the groove 108, the safety device comprising the parts 113 to 116 comes into operation. The spring 116 is compressed, the rod head 115 moves to the left as viewed in FIGURE 6 and rotates a loom stop motion lever 117 clockwise; the shaft 118 to which the lever 117 is fixed actuates a device which disconnects the main shaft of the loom from the driving motor and brakes the main shaft.

The locking disc 101 and the locking roller 103 are shown on a larger scale in FIGURE 7. Since the change drum 71, and hence the locking disc 101, are subject to the action of the accumulator elements 80, 81 (power means), either the upper or the lower wall of the notch 102a contacts the locking roller 103. 7

At the point of contact r between the moving element (the locking disc 101) and the supporting means (the locking roller 103), force is transmitted from the moving element to the supporting means. The point of contact r now travels, not only along a straight portion 119 and rounded portion 120 of the wall of the notch, but also along the roller-103 with reference to its pivot point 121 and the lever 104. Moreover, before the normal separation of the moving element from the supporting means occurs, i.e., when the pivot point 121 is located at a distance equal to the radius of the roller 103 from the outer periphery 122 of the locking disc 101, the roller 103 rides on the edge 123 of the rounded part 120. Since during this time the direction of rotation 124 of the locking disc 101 is oriented transversely to the direction of rotation 125 of the locking roller 103, a disturbing force occurs, in this case, by the moving element upon the supporting means.

It has in fact been found that, when the locking roller 103 was withdrawn from a notch 102 in order to release the drum 71 to change the weft thread to be inserted, the safety device comprising the parts 113 to 117 responded and the weaving machine was stopped by rotation of the shaft 118.

When the locking roller 103 is withdrawn from a notch 102, there appears to be nothing interfering with it in such a way as to cause the pivot point 112 to slide to the left. The rod 107 moves to the right when the roller 103 is withdrawn; therefore, if the roller 103 encounters an obstacle in moving to the left, it would appear necessary for the pivot pin 112 to be able to escape to the right although this is impossible'because the head 115 of the rod 114 is abutting the element 105. The disturbance is, in fact, caused by the fact that, due to a wedge effect in the final phase of withdrawal of the locking roller 103 from the notch 102, the force exerted by the moving element (the locking disc 101) upon the supporting means (the locking roller 103) at the common point of contact r results in a force on the pin 112 directed towards the left which overcomes the force of the spring 116 and produces a sliding of the fork 113 and of the rod 114, so that an unnecessary stoppage of the weaving machine is initiated by rotation of the stop motion shaft 118. In order to eliminate this disturbance, a premature separation of the supporting means from the moving element is brought about according to the invention, as in the first case (FIGURES 1 to 4).

FIGURE 8 shows the displacement of the common point of contact r when the roller 103 rolls on the wall 119, 120. In the straight portion 119, the point r is always vertically below the rotation point 121 of the roller 103 (path m to the right of m in FIGURE 8). On the other hand, when rolling along the curved portion 120, the point of contact r to r-; is located on the line connecting the instantaneous pivot points m to m and the instantaneous centres of curvature M to 14 of the rounded portion 120.

In the position m the common point of contact r has reached the edge 123, the roller 103 and the rounded portion 120 still possess a common tangent, and r is still located upon the line connecting m to u Additional points 8 and 9 have been plotted, but on the line r these lie outside the outer periphery 122. At the point 111 that position of the roller 103 is reached where the roller just remains in contact with the outer periphery 122 and its separation from the locking disc 101 normally occurs.

Beyond r the points r to r have been plotted; these points correspond to the progressive position of the edge 123 which remains in contact with the peripheral surface of the roller 103 from r onwards, until its rotation point 121 has reached the position m In order to show the forces and relative travels at the various points of contact, the curve r has been plotted with the same ordinates as the curve r but with the abscissae to twice the scale, in order to avoid overlapping of the triangles of forces and travel components above the curve r for the sake of clarity.

Above the curve r triangles of motion W have been plotted; the instantaneous sliding of the common point of contact occurs along the common tangent. The vertical components of motion show the rotation of the locking disc 101, and the horizontal components show the withdrawal of the locking roller 103.

In the case of the triangles of forces K which have been plotted above the triangles of motion W, the vertical force is constant because the power accumulator elements 80, 81 impart a virtually constant torque to the change drum 71 within the range of displacement. The force component transmitted to the locking roller 103 lies upon the line from u to m for the points r to r The horizontal force component of the triangles K increases from 1 to 7. At the top of FIGURE 8, triangles of motion +W and triangles of forces +K are shown for the positions of the point of contact from +1 to +7, where the roller 103 only just remains in contact with the edge 123. These triangles of forces show a far greater increase than those for positions r to r-;.

The horizontal force components of K and +K act upon the roller lever 104 at the rotation point 121, and because they are directed towards the left, the spring 116 is acted upon with even greater force via the pivot point 112, the fork 113 and the rod 114, because of the lever effect. Now, as soon as the force produced at the pivot point 112 by the horizontal force components exceeds the force of the spring 116, the head 115 is moved to the left and the loom stop motion is initiated unnecessarily by rotating the stop-motion shaft 118.

According to the invention, therefore, the drive of the lever 104 by the groove 108 in the disc 109 is so devised that, even before the rotation point 121 has reached the position m in FIGURE 8, a separation of the supporting means (the locking roller 103) from the moving element (the locking disc 101) occurs prematurely.

In FIGURE 9, the line r represents the movement of the point of contact of the locking disc 101 in the direction of travel of the locking roller 103 while the line r represents the corresponding movement of the point of contact of the locking roller 103. This line results from the successive addition of the horizontal travel components of the travel triangles W and +W in FIGURE 8.

In order to eliminate the possibility of any undesired cutting-out of the loom, the separation of the locking roller 103 must be initiated before the horizontal force component can generate, at the pivot point 112, a dynamic effect equal to the force of the spring 116. It is desirable to provide a certain safety margin. Before the further movement of the locking roller 103 and of the locking disc 101, it is sufiicient to maintain the separation and merely to effect, for example, a small distance it between the line r and the line r this distance n can be determined on the basis of the oscillations to be anticipated when the locking roller 103 is withdrawn from the notch 102. The distance 11 may be constant or may increase. The velocity of the movement of the roller 103 towards the left may actually diminish, since the magnitude of the horizontal travel component, directed towards the left, of the travel triangles W and +W actually diminishes rapidly.

The points r and r to r are more likely to be considered as a commencement of the separation. In this case, it is unimportant whether the notches 102a to 102d have a rounded portion at the end, or whether such is omitted in order to shorten the travel of the locking roller 103.

A third application of the invention is illustrated in FIGURE 10. As is known, the thread feeders 99a to 99d slidably mounted in the change drum 71, FIGURE 6, occupy the left-hand terminal position during changing of the weft thread. The feeder 99d which is brought into the weft line is caught by .a nose 128 on a carriage 126, which executes a reciprocating motion along a guideway 127. The carriage is connected by a link 129 to the left-hand end of a retractor lever 130. The lever 130 swings about a fixed axis 131 and carries a pin 132 for supporting a roller 133. The latter travels in the groove 134 of a grooved drum 135, the axis 136 of which is driven at constant speed by the main shaft of the weaving machine.

From the lower terminal position V in FIGURE 10, which corresponds to the left-hand terminal position in FIGURE 6, the feeder 99d, the closed thread clamp of which holds the weft thread to be inserted, is at first pushed by the lever 130 sufficiently far towards the shuttle 100, FIGURE 6, that the weft thread can be gripped in known manner by the shuttle 100 and released by the feeder 99d. After the shuttle 100 has been picked, the feeder 99d without a weft thread is moved by the lever 130 into the position VI at the edge 137 of the shed. There it grips the weft thread which is severed in known manner between the edge 137 and the feeder 99d, whereafter the feeder 990., the thread clamp whereof firmly holds the severed end of the thread, is returned by the drum and the lever 130 from the position VI into the position V, the weft thread being maintained under tension in known manner by a thread tensioner. Thus the feeder acts as a retractor for the end of the weft thread attached to the bobbin and will be described as a retractor hereafter.

The lever 130 is connected at the right-hand end to a piston 137 in a cylinder 138, which is secured to the wall of a housing together with a bracket 139 for the swing axis 131. A pressurized medium, air or liquid, is fed to the cylinder 138 through a conduit 141, and forms the power is subject toall the fluctuations in angular velocity of that shaft.

During the forward movement towards the shed 137, these oscillations are insignificant. However, it has been found that during the return movement of the thread feeder with the weft thread attached, the oscillations produce vibrations in the retractor which cause undesired brief opening of the thread clamp and loss of the thread. This is very objectionable because no broken-end detector is provided at this part of the loom; the loose thread end may easily enter the guideways of the retractor 99, thereby causing a disturbance of considerable duration.

FIGURE 11 shows the development of the groove 134 in the drum 135. The direction of rotation is indicated, both in FIGURE 10 and in FIGURE 11, by the arrow 142. The grooved portion 134a controls the forward movement of the roller 133 and of the lever 130 from the position V to the position VI. In this portion of the groove an operative connection exists between the moving element (the roller 133) and the supporting means (the groove 134). The movement of the roller 133 is positively guided by the groove 134a.

During the return movement of the lever 130 from the position VI to the position V the roller 133 lies in the grooved portion 13411 which is enlarged relative to portion 134a. There is a clearance between the walls 143 and 144 and the roller 133, so that a separation of the moving element (the roller 133) and the supporting means (the groove 134b) is made possible and, according to the invention, the roller 133 can be moved exclusively by the power means, namely, the pressure medium in the cylinder 138. 7

FIGURE 12 shows, on the right-hand side, the velocity diagram for the roller 133 under the action of the air pressure in the cylinder 138, from the position 2 to the position z The roller 133 is accelerated from position z on and its velocity increases from v to v At the time the roller 133 moves at the velocity v the roller is in the position z and has traveled three, quarters of the distance z. From position z the roller is decelerated until it reaches its terminal position z To effect this deceleration also the upper part of the cylinder 138 is closed. A groove 146 is provided in the piston rod 145 for connecting the upper chamber 147 to the outside when the piston 137 ascends. However, the groove 146 does not extend all the way down to piston 137 but only so far that the lower end of the groove terminates in the piston rod guide 148 during the last quarter of the tip-stroke of the piston 137 so that the chamber 147 is sealed to effect deceleration by air compression. Because of the deceleration the entry into the straight portion of the groove 134, which follows the portion 13411, is free from shock. The effect of this deceleration is smoother than the effect of a stop element if such were provided for the lever 130 at the terminal position V.

The left-hand portion of the diagram in FIGURE 12 shows the points of contact 11 on the moving element (the roller 133) when it moves solely by the action of the air pressure in the cylinder 138. The curve a illustrates the position of the points of contact at the wall of the enlarged groove 143, and the curve u shows the points of contact at the wall 144.

The magnitude of the distance between u 'and 11 during the acceleration, and between 11 and u during the deceleration, is determined according to the anticipated oscillations. Instead of the curve M and of the curve u' space may also be left on both sides along the total length of 11 as the two curves u show.

I claim:

I. A weaving machine comprising:

a moving element,

a power means connected to said moving element for 12 moving said moving element in a path at a predetermined rate of speed, a supporting means for contacting said moving element at a mutual point of contact in a non-positive con-.

nection,

means operatively connected to said supporting means for moving said supporting means in said path simultaneously with said moving element and against the action of said power means, said operatively connected means and in the opposite direction having accelerating means for moving said supporting means in said path out of contact with said moving element during simultaneous movements thereof through said power means whereby said supporting means is separated from said moving element before said moving element reaches a position of action near the end of 7 said path.

2. A weaving machine as set forth in claim 1 wherein said operatively connected means further includes a drive means connected to said accelerating means driving said accelerating means; and said accelerating means includes a steering arrangement having a steering groove With an inclination in the sense of an augmentation of the moving of said supporting means for moving said supporting means out of contact with said moving element.

3. A weaving machine as set forthin claim 1 wherein said supporting means is separated from said moving element a distance greater than the maximum amplitude oscillation of said supporting means during separation whereby the supporting means is maintained out of contact with said moving element during simultaneous movement.

4. A weaving machine comprising a plurality of healds,

a card dobby including a card band,

a plurality of reading needles for reading said card band,

a plurality of lifting needles each supporting a respective reading needle,

a pulling bar contacting said lifting needles for pulling said reading needles from said card band,

a lifting rail for lifting said lifting needles,

a steering arrangement operatively connected to said pulling bar for separating said pulling bar from said lifting needles during movement of said pulling bar and said lifting needles in a common direction, and

power means for pushing said lifting needles in said common direction.

5. A weaving machine comprising 'a a plurality of gripper shuttles,

means including a retractor for feeding weft'threa-d to said shuttles,

a lever connected to said retractor for actuation of said retractor,

a rotatable drum means operatively connected to said drive means,

said drum means including a cam surface means,

drive means,

a cam follower mounted on said lever and projecting 7 onto said cam surface means for engagement therewith whereby said lever is moved according to the configuration of said cam surface means, said cam surface means also having an inclination in the sense of an augmentation of the movement of said cam follower therein for separating said cam follower from said cam surface during simultaneous but inde pendent movements of said cam follower, and power means for moving said lever and cam follower independently of said cam surface means.

6. A weaving machine as set forth in claim 5 wherein said cam surface means is in the form of a groove having an S-curve configuration and wherein said inclination changes from one side of said S-curve to the other.

7. A weaving machine comprising a weft thread changing means including an energy accumulator forming a power means, a locking disc operatively connected to said energy accumulator, said disc having a plurality of indentations therein,

a drive means, a steering arrangement connected to said drive means, a locking roller operatively connected to said steering arrangement for movement thereby reciprocably with respect to at least one of said indentations, said steering arrangement including a steering groove having an inclination in the sense of an augmentation of the movement of said locking roller for separating said locking roller from said locking disc during movement of said locking disc whereby the separation of said locking roller from said locking disc is of action.

References Cited UNITED STATES PATENTS Morris 139-68 Wild 139-68 X Baster 74-567 Weiner et al. 74-567 Moessinger 139-145 Jones et a1. 74-567 Bergstrom et al 139-260 Pfarrwaller 74-567 Floyd et a1 139-145 MERVIN STEIN, Primary Examiner. effected prior to said locking disc reaching a position 15 ONALD PARKER, 5 JAUDON Assistant Examiners. 

1. A WEAVING MAHICNE COMPRISING: A MOVING ELEMENT, A POWER MEANS CONNECTED TO SAID MOVING ELEMENT FOR MOVING SAID MOVING ELEMENT IN A PATH AT A PREDETERMINED RATE OF SPEED, A SUPPORTING MEANS FOR CONTACTING SAID MOVING ELEMENT AT A MUTUAL POINT OF CONTACT IN A NON-POSITIVE CONNECTION, MEANS OPERATIVELY CONNECTED TO SAID SUPPORTING MEANS FOR MOVING SAID SUPPORTING MEANS IN SAID PATH SIMULTANEOUSLY WITH SAID MOVING ELEMENT AND AGAINST THE ACTION OF SAID POWER MEANS, SAID OPERATIVELY CONNECTED MEANS AND IN THE OPPOSITE DIRECTION HAVING ACCELERATING MEANS FOR MOVING SAID SUPPORTING MEANS IN SAID PATH OUT OF CONTACT WITH SAID MOVING ELEMENT DURING SIMULTANEOUS MOVEMENTS THEREOF THROUGH SAID POWER MEANS WHEREBY SAID SUPPORTING MEANS IS SEPARATED FROM SAID MOVING ELEMENT BEFORE SAID MOVING ELEMENT REACHES A POSITION OF ACTION NEAR THE END OF SAID PATH. 